BACKGROUND

To cross streets safely, pedestrians with vision disabilities (including those with hearing disabilities) must quickly and accurately determine the onset of the walk indication. They must also be able to recognize and determine, by sound, the trajectories of vehicles that may intrude into their path of travel to allow them to take appropriate action, such as delaying the onset of crossing or pausing while crossing.

In recent years, state departments of transportation have made great efforts to enhance accessibility for pedestrians with vision disabilities. These efforts often contemplate implementing various features of Accessible Pedestrian Signals (APS), such as changing the default walk indication from a percussive tone to a speech message and incorporating audible countdowns during the pedestrian change interval. However, these features are not fully aligned with the requirements outlined in the current Manual on Uniform Traffic Control Devices (MUTCD).

While the existing MUTCD standards do specify percussive tones for the walk interval, and the return of the locator tone during the clearance interval to prevent auditory masking of vehicle sounds and reduce cognitive load, groups representing vision-impaired individuals have suggested that speech messages and audible countdowns could provide more descriptive auditory cues. These enhancements may improve safety by increasing accessibility, confidence, and independence for APS users.

Research is needed to provide empirical evidence on whether these proposed changes enhance the safety and accessibility of APS for pedestrians with vision disabilities.

OBJECTIVE

The objective of the project is to determine the most effective types of indications for APS to enhance the safety and accessibility of pedestrians with vision disabilities using research on human factors through a combination of laboratory and field experiments.

At a minimum, the research shall address:

• Whether a speech message or percussive tone is more beneficial as the APS walk indication, and
• Whether an audible countdown or locator tone is more beneficial for accessible and safe pedestrian crossing during the pedestrian change interval.

Accomplishment of the project objective will require at least the following tasks.

TASKS

The sequencing of tasks and deliverables shall be structured for delivery in quarterly progress report submissions in which specific deliverables are requested or proposed. Three project phases will occur, with a 30-month duration broken into 10 3-month quarters. The proposer may re-sequence the timeline according to their best decision-making.

PHASE I – PLANNING

In Phase I, the research team shall review, document, and synthesize existing research on APS audible indications, including the effectiveness of percussive tones versus speech messages and audible countdowns during the pedestrian change interval. By the end of the first quarter, the research team shall propose the testing sites for the field research to the NCHRP for review and approval and shall meet with the NCHRP virtually to discuss the site selection process. The research team shall also develop a laboratory and field research methodology, which may include qualitative analysis from the field research, such as the optimal volume and general participants feedback, to achieve the project objective to be executed in Phase II.

The research team shall obtain approval from an Institutional Review Board (IRB) and experimentation approval from the Federal Highway Administration (FHWA) to perform Phase II research. More specifically, the research team shall:

• Obtain IRB approval, ensuring ethical considerations are met for research participants, and include consent forms, safety measures, and procedures for data confidentiality (see Special Note A);
• Obtain permission from transportation agencies to perform the research; and
• Support transportation agencies obtaining the FHWA’s experimentation approval to assess pedestrian crossing behavior at intersections under different APS audible indication conditions at a minimum of three testing sites with good geographical and environmental diversity.

Proposers shall clearly articulate their intended schedule of deliverables. The Phase I deliverables shall include, at a minimum, the following: (1) an amplified research plan, (2) a kick-off meeting with summary notes, (3) a literature review and research gaps memo, and (4) a laboratory and field research methodology to be executed in Phase II. 

At the end of Phase I, the research team shall deliver Interim Report No. 1 and an updated Phase II work plan. Phase I is estimated to be accomplished within 9 months.

PHASE II – EXECUTION

Phase II of the project will focus on executing the research methodology per the approved Interim Report No.1.

At the end of Phase II, the research team shall deliver Interim Report No. 2 and an updated Phase III work plan with a virtual interim meeting.

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PHASE III – FINAL DELIVERABLES

Prepare a draft report with recommendations for the selection, installation, and settings of APS audible indications based on the Phase II research findings. Additionally, submit draft language following the MUTCD’s format and structure to support the needs and efforts related to the pedestrian signals of the American Association of State Highway and Transportation Officials (AASHTO) Committee on Traffic Engineering (COD) (hereafter called AASHTO Deliverable). The NCHRP will review and approve the draft AASHTO Deliverable.

Present the approved AASHTO Deliverable to the AASHTO COD and the National Committee on Uniform Traffic Control Devices (NCUTCD) at their respective annual meetings or via teleconference. Revise the draft report and AASHTO Deliverable after consideration of the review comments.

At a minimum, the final deliverables shall include: 

• A final research report documenting the entire research effort, findings, and recommendations for the selection, installation, and settings of APS audible indications;
• The AASHTO Deliverable;
• Recommendations for future research;
• A presentation with speaker notes summarizing the project and clearly illustrating for the audience how the research can be applied in their organization; and
• A technical memorandum titled “Implementation of Research Findings and Products”.

STATUS: Proposals have been received in response to the RFP. The project panel will meet to select a contractor to perform the work.